Composite drive beam for surgical stapling

ABSTRACT

An end effector includes a mounting portion that mounts to a surgical stapling apparatus, first and second jaw members extending distally from the mounting portion, a drive beam engagable with the first and second jaw members, and a threaded drive screw. The first jaw member includes a first tissue engaging surface and the second jaw member supports a fastener cartridge. The fastener cartridge includes a second tissue engaging surface that defines fastener retaining slots that support fasteners. The drive beam includes a retention foot formed of a first material. The retention foot defines a threaded bore that supports a threaded insert formed of a second material. The threaded drive screw is threadably engaged with the threaded insert and is rotatable to distally advance the drive beam along the threaded drive screw to fire and form the fasteners.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/507,886, filed Oct. 7, 2014, now U.S. Pat. No. 9,629,631, whichclaims the benefit of U.S. Provisional Patent Application No.62/019,560, filed Jul. 1, 2014, the entire disclosure of each of whichis incorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to surgical apparatus, devices and/orsystems for performing endoscopic surgical procedures and methods of usethereof. More specifically, the present disclosure relates toelectromechanical, hand-held surgical apparatus, devices and/or systemsconfigured for use with removable disposable loading units and/or singleuse loading units for clamping, cutting, and/or stapling tissue.

BACKGROUND

A number of surgical device manufacturers have developed product lineswith proprietary drive systems for operating and/or manipulatingelectromechanical surgical devices. Some electromechanical surgicaldevices include a handle assembly, which is reusable, and replaceableloading units and/or single use loading units or the like that areselectively connected to the handle assembly prior to use and thendisconnected from the handle assembly following use, in order to bedisposed of or in some instances sterilized for re-use. These loadingunits can include jaw members that support an actuatable drive beam toeffectuate clamping, cutting, and/or stapling of tissue.

Many of these electromechanical surgical devices, or components thereof,are relatively expensive to manufacture, purchase, and/or operate. Thereis a desire by manufacturers and end users to develop electromechanicalsurgical devices that are relatively inexpensive to manufacture,purchase, and/or operate.

Accordingly, a need exists for electromechanical surgical apparatus,devices and/or systems that are relatively economical to develop andmanufacture, to store and ship, as well as economical and convenient topurchase and use from the end user's perspective.

SUMMARY

According to one aspect of the present disclosure, an end effector of asurgical stapling apparatus is provided. The end effector includes amounting portion adapted to selectively mount to the surgical staplingapparatus, first and second jaw members extending distally from themounting portion, a drive beam engagable with the first and second jawmembers, and a threaded drive screw.

The first jaw member includes a first tissue engaging surface anddefines a ramp. The second jaw member is adapted to support a fastenercartridge. The fastener cartridge includes a second tissue engagingsurface that defines fastener retaining slots. The fastener retainingslots support a plurality of fasteners.

The drive beam is engagable with the ramp of the first jaw member tomaintain the first jaw member and the second jaw member in anapproximated state as the drive beam distally translates along the firstand second jaw members.

The drive beam includes a retention foot formed of a first material. Inembodiments, the first material includes metallic material. In someembodiments, the first material includes stainless steel. The retentionfoot defines a threaded bore that supports a threaded insert formed of asecond material. In embodiments, the second material includes polymericmaterial. In some embodiments, the second material includes polyetherether ketone. The threaded bore includes internal threads that extendfrom an inner surface of the threaded bore. The internal threads engageexternal threads extending from an outer surface of the threaded insert.The threaded insert includes opposite ends. In embodiments, each of theopposite ends of the threaded insert includes locking flanges extendingtherefrom to fix the threaded insert to the retention foot.

In some embodiments, the threaded insert includes internal threadsextending from an internal surface of the threaded insert. Inembodiments, each of the internal threads of the threaded insert definesan internal peak and each of the external threads of the threaded insertdefines an external peak, each internal peak being adjacent to, andlongitudinally offset from, one of the external peaks.

In embodiments, the drive beam supports a knife adapted to cut tissue asthe drive beam translates along the threaded drive screw. In someembodiments, the drive beam includes a lateral projecting member,wherein at least portions of the lateral projecting member are formed ofa polymeric material.

The threaded drive screw is threadably engaged with the threaded insertof the drive beam. The threaded drive screw is rotatable to selectivelydistally advance the drive beam along the threaded drive screw to firethe plurality of fasteners from the fastener retaining slots of thefastener cartridge and form the plurality of fasteners against the firsttissue engaging surface of the first jaw member.

In another aspect of the present disclosure, a powered surgical staplingapparatus includes a handle assembly, a shaft assembly extendingdistally from the handle assembly, and an end effector selectivelydetachable from the shaft assembly.

Other aspects, features, and advantages will be apparent from thedescription, the drawings, and the claims that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosureand, together with a general description of the disclosure given above,and the detailed description of the embodiment(s) given below, serve toexplain the principles of the disclosure, wherein:

FIG. 1 is a perspective view of an electromechanical surgical systemaccording to the principles of the present disclosure;

FIG. 2 is a perspective view, with parts separated, of theelectromechanical surgical system of FIG. 1;

FIG. 3 is a front, perspective view of an end effector of theelectromechanical surgical system of FIGS. 1 and 2;

FIG. 4 is a rear, perspective view of the end effector of FIG. 3;

FIG. 5 is a perspective view, with parts separated, of the end effectorof FIGS. 3 and 4;

FIG. 6 is a side, cross-sectional, perspective view of the end effectorof FIGS. 3-5, as taken through 6-6 of FIG. 4, showing the end effectorin an unapproximated state;

FIG. 7 is an enlarged view of the indicated area of detail shown in FIG.6;

FIG. 8 is a side, cross-sectional view of the end effector showing adrive beam thereof in a partially advanced position;

FIG. 9 is an enlarged view of the indicated area of detail shown in FIG.8;

FIG. 10 is a side, cross-sectional view of the end effector in anapproximated state with the drive beam thereof shown in a partiallyadvanced position;

FIG. 11 is an enlarged view of the indicated area of detail shown inFIG. 10;

FIG. 12 is an enlarged, partial, cross-sectional view of the endeffector showing the drive beam partially advanced;

FIG. 13 a side, cross-sectional view of the end effector in anapproximated state with the drive beam thereof shown in a distallyadvanced position;

FIG. 14 is a rear, perspective view of an embodiment of a drive beam inaccordance with the principles of the present disclosure;

FIG. 15 is a side, cross-sectional view of the drive beam of FIG. 14, astaken through line 15-15 of FIG. 14; and

FIG. 16 is a rear, perspective, cross-sectional view of the drive beamof FIG. 14, as taken through line 16-16 of FIG. 14.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed electromechanical surgicalsystem, apparatus and/or device are described in detail with referenceto the drawings, in which like reference numerals designate identical orcorresponding elements in each of the several views. As used herein theterm “distal” refers to that portion of the electromechanical surgicalsystem, apparatus and/or device, or component thereof, that are fartherfrom the user, while the term “proximal” refers to that portion of theelectromechanical surgical system, apparatus and/or device, or componentthereof, that are closer to the user.

Referring initially to FIGS. 1 and 2, an electromechanical, hand-held,powered surgical system is shown and generally designated 10.Electromechanical surgical system 10 includes a surgical apparatus ordevice in the form of an electromechanical, hand-held, powered surgicalinstrument 100 that is configured for selective attachment thereto of aplurality of different end effectors 400, via a shaft assembly 200 thatare each configured for actuation and manipulation by theelectromechanical, hand-held, powered surgical instrument 100. Inparticular, surgical instrument 100 is configured for selectiveconnection with an articulation assembly 300 of shaft assembly 200, and,in turn, shaft assembly 200 is configured for selective connection withany one of a plurality of different end effectors 400 via articulationassembly 300.

Reference may be made to U.S. Patent Application Publication No.2009/0101692, U.S. Patent Application Publication No. 2011/0121049, andU.S. Patent Application Publication No. 2013/0098966, the entire contentof each of which is hereby incorporated herein by reference, for adetailed description of the construction and operation of exemplaryelectromechanical, hand-held, powered surgical instruments, thecomponents of which are combinable and/or interchangeable with one ormore components of powered surgical system 10 described herein.

Generally, as illustrated in FIGS. 1 and 2, surgical instrument 100includes an instrument housing 102 having a lower housing portion 104,an intermediate housing portion 106 extending from and/or supported onlower housing portion 104, and an upper housing portion 108 extendingfrom and/or supported on intermediate housing portion 106. The surgicalinstrument 100 has a controller (not shown) for controlling certainfunctions of the surgical system, collecting data, and performing otherfunctions. Instrument housing 102 defines a cavity (not shown) thereinin which a circuit board (not shown) and a drive mechanism (not shown)are situated.

The circuit board is configured to control the various operations ofsurgical instrument 100, as will be set forth in additional detailbelow. In accordance with the present disclosure, instrument housing 102provides a housing in which a rechargeable battery (not shown), isremovably situated. The battery is configured to supply power to any ofthe electrical components of surgical instrument 100.

Upper housing portion 108 of instrument housing 102 has a nose orconnecting portion 108 a configured to accept a corresponding shaftcoupling assembly 204 of transmission housing 202 of shaft assembly 200.As seen in FIG. 2, connecting portion 108 a of upper housing portion 108of surgical instrument 100 defines a cylindrical recess 108 b thatreceives shaft coupling assembly 204 of transmission housing 202 ofshaft assembly 200 when shaft assembly 200 is mated to surgicalinstrument 100. The connecting portion 108 a of the surgical instrument100 has at least one rotatable drive member. In some embodiments,connecting portion 108 a houses a plurality of rotatable drive membersor connectors (not shown), each drive member of the plurality of drivemembers can be independently, and/or dependently, actuatable androtatable by the drive mechanism (not shown) housed within instrumenthousing 102.

Upper housing portion 108 of instrument housing 102 provides a housingin which the drive mechanism (not shown) is situated. The drivemechanism is configured to drive shafts and/or gear components in orderto perform the various operations of surgical instrument 100. Inparticular, the drive mechanism is configured to drive shafts and/orgear components in order to selectively move end effector 400 relativeto shaft assembly 200; to rotate anvil assembly 200 and/or end effector400, about a longitudinal axis “X1” (see FIGS. 1 and 2), relative toinstrument housing 102; to move a first/upper jaw member or anvilassembly 410 of end effector 400 relative to a second/lower jaw memberor cartridge assembly 420 of end effector 400; to articulate and/orrotate the shaft assembly 200; and/or to fire a fastener cartridge 420 awithin cartridge assembly 420 of end effector 400.

In accordance with the present disclosure, the drive mechanism mayinclude a selector gearbox assembly (not shown); a function selectionmodule (not shown), located proximal to the selector gearbox assembly,that functions to selectively move gear elements within the selectorgearbox assembly into engagement with a second motor (not shown). Thedrive mechanism may be configured to selectively drive one of drivemembers or connectors of surgical instrument 100, at a given time.

As illustrated in FIGS. 1 and 2, instrument housing 102 supports a pairof finger-actuated control buttons 124, 126 and/or rocker device(s) 130(only one rocker device being shown). Each one of the control buttons124, 126 and rocker device(s) 130 includes a respective magnet (notshown) that is moved by the actuation of an operator. In addition, thecircuit board (not shown) housed in instrument housing 102 includes, foreach one of the control buttons 124, 126 and rocker device(s) 130,respective Hall-effect switches (not shown) that are actuated by themovement of the magnets in the control buttons 124, 126 and rockerdevice(s) 130. The actuation of Hall-effect switch (not shown),corresponding to control buttons 124, 126 causes the circuit board toprovide appropriate signals to the function selection module and theinput drive component of the drive mechanism to open/close end effector400 and/or to fire a stapling/cutting cartridge within end effector 400.

Similarly, the actuation of the Hall-effect switch, corresponding torocker device 130, causes the circuit board to provide appropriatesignals to the function selection module and the input drive componentof the drive mechanism to rotate end effector 400 relative to shaftassembly 200 or rotate end effector 400 and shaft assembly 200 relativeto instrument housing 102 of surgical instrument 100. Specifically,movement of rocker device 130 in a first direction causes end effector400 and/or shaft assembly 200 to rotate relative to instrument housing102 in a first direction, while movement of rocker device 130 in anopposite, e.g., second, direction causes end effector 400 and/or shaftassembly 200 to rotate relative to instrument housing 102 in anopposite, e.g., second, direction.

Turning now to FIGS. 3-13, end effector 400 is shown and described. Endeffector 400 is configured and adapted to apply a plurality of linearrows of fasteners “F” (e.g., staples, see FIG. 5). In certainembodiments, the fasteners are of various sizes, and, in certainembodiments, the fasteners have various lengths or rows, e.g., about 30,45 and 60 mm in length.

As seen in FIGS. 3 and 4, end effector 400 includes a mounting portion430 coupled to a jaw assembly 415. A proximal end portion of mountingportion 430 is configured for selective connection to a distal endportion of shaft assembly 200 (e.g., articulation assembly 300) that hascomplementary structure formed thereon. Jaw assembly 415 is connectedto, and extends distally from, mounting portion 430. Jaw assembly 415,as will be discussed in greater detail below, includes lower jaw member420, which is configured to selectively support fastener cartridge 420 atherein, and upper jaw member 410, each of which is secured to mountingportion 430 to enable relative movement between upper and lower jawmembers 410, 420. Jaw assembly 415 is pivotally movable to orient upperand lower jaw members 410, 420 between approximated and unapproximatedstates.

With reference to FIG. 5, upper jaw member 410 includes an anvil body410 a with a tissue engaging/fastener forming surface 411 including aplurality of staple forming pockets (not shown), arranged inlongitudinally extending rows and configured to form the fasteners upona firing of end effector 400, as appreciated by one skilled in the art.Anvil body 410 a supports a leaf spring assembly 412 and a leverassembly 414 that are supported within a chamber 410 b of body 410 a.Leaf spring assembly 412 and lever assembly 414 are enclosed withinchamber 410 b by a cover 410 c that is selectively removable from body410 a. Together, leaf spring assembly 412 and lever assembly 414function to bias jaw assembly 415 in the unapproximated state and enablepivotal movement of the jaw assembly 415 between the approximated andunapproximated states as described in greater detail herein.

Leaf spring assembly 412 includes a leaf spring 412 a that is mounted tobody 410 a at a first end of leaf spring 412 a by a mounting plate 412 band a fastener 412 c. Leaf spring 412 a extends to an engagement tip 412d at a second end of leaf spring 412 a that can have any suitableconfiguration such as a curvilinear scoop.

Lever assembly 414 includes a lever 414 a that defines a pin channel 414c on one end thereof and a distal tip 414 b on an opposite end thereof.Lever 414 is pivotally mounted to anvil body 410 a by a pin 414 d thatis received through pin channel 414 c of lever 414 a and a pin channel410 d defined in anvil body 410 a.

Anvil body 410 a defines a plurality of bores on a proximal end of anvilbody 410 a including a drive bore 410 e that receives a drive assembly416, a pair of plunger bores 410 f that receives a pair of plungerassemblies 418, and a electrical contact bore 410 g that receives anelectrical contact member 417 that functions to electrically communicatewith instrument housing 102 when end effector 400 is secured to shaftassembly 200. Drive assembly 416 includes a drive member 416 a, a gearmember 416 b coupled to drive member 416 a, and a mounting plate 416 cthat supports drive member 416 a and gear member 416 b. Each plungerassembly of the pair of plunger assemblies 418 includes a plunger 418 athat receives a spring 418 b that functions to spring bias plunger 418 ain a distal direction to facilitate securement of fastener cartridge 420a to cartridge assembly 420. Plunger 418 a defines a pin slot 418 c thatreceives a pin 418 d to secure each plunger assembly within a respectiveone of the pair of plunger bores 410 f when pin 418 d is received withina pin channel 410 h defined within anvil body 410 a.

Lower jaw member 420 is configured and adapted to selectively receivefastener cartridge 420 a. Fastener cartridge 420 a includes a tissueengaging surface 423 a that defines a plurality of rows of fastenerretaining slots 423 b adapted to support the plurality of fasteners “F”(and a plurality of staple pushers, not shown, but can be appreciated bythose skilled in art). Fastener cartridge 420 a also includes alongitudinally extending knife slot 423 c disposed between pairs of rowsof fastener retaining slots 423 b that is adapted to enable drive beam426 to axially translate therethrough.

Lower jaw member 420 includes a mounting member 420 b, in the form of achannel that supports fastener cartridge 420 a and a base member 420 ccouplable to mounting member 420 b. Mounting member 420 b includes amounting body 421 having a pair of wings 421 a that extends proximallytherefrom. The pair of wings 421 a defines a fastener channel 421 btherethrough that is dimensioned to receive fasteners 440 advanced intoa pair of passages 410 i defined in upper jaw member 410 for securingupper jaw member 410 to lower jaw member 420. A slot 421 c and a screwpassage 421 d are defined in a plate 421 e of mounting body 421positioned adjacent to the pair of wings 421 a.

An actuation sled 422 is supported by lower jaw member 420 and isadapted to advance through fastener cartridge 420 a to fire theplurality of fasteners supported with fastener cartridge 420 a as oneskilled in the art will appreciate. Lower jaw member 420 rotatablysupports a drive screw 424 therein that extends substantially an entirelength of lower jaw member 420. Drive screw 424 is threadably engagedwith drive beam 426, which is axially slidably supported in lower jawmember 420 between proximal and distal positions in response to rotationof drive screw 424, as described in greater detail below. Drive screw424 includes a multi-faceted head 424 a, a pair of retention members 424b that define an annular channel 424 c therebetween, and a distallyextending threaded shaft 424 d. Drive screw 424 extends through screwpassage 421 d so that a bracket 428, which defines a U-shaped channel428 a therethrough, secures drive screw 424 to mounting member 420 bwhen bracket 428 is received in slot 421 c and positioned within annularchannel 424 c. Bracket 428 and mounting member 420 b cooperate toaxially and lateral fix drive screw 424 in lower jaw member 420 whileenabling drive screw 424 to rotate.

Drive beam 426 has a substantially I-shaped cross-sectional profileconfigured to progressively approximate lower jaw member 420 and upperjaw member 410 as drive beam 426 travels through knife slot 423 c infastener cartridge 420 a. Drive beam 426 functions to axially displaceactuation sled 422 through lower jaw member 420 and includes a retentionfoot 426 a having an internally threaded bore 426 f, a verticallyoriented support strut 426 b supported on retention foot 426 a, and alateral projecting member 426 c formed atop support strut 426 b. Lateralprojecting member 426 c defines a notch 426 d formed in an upper surfacethereof. Vertically oriented support strut 426 b supports a knife 426 ethereon that is adapted to cut tissue.

FIG. 5 illustrates that mounting portion 430 is secured to the proximalend portion of upper jaw member 410. Mounting portion 430 includes afirst member 432, a second member 434, and a third member 436 that arecoupled together and support a spring assembly 438. Spring assembly 438includes a plunger 438 a and a spring 438 b.

Referring now to FIGS. 6 and 7, end effector 400 is shown in an initialand/or unapproximated state, in which upper jaw member 410 is spacedfrom lower jaw member 420 relative to a longitudinal axis “X2” definedthrough end effector 400. In the unapproximated state, lower jaw member420 is positioned at an acute angle (e.g., 15 degrees) relative to upperjaw member 410, drive screw 424 is disposed at an acute angle relativeto mounting portion 430, and head 424 a of drive screw 424 is supportedat an acute angle within a bore 416 d defined by drive member 416 a.

As depicted in FIG. 7, when end effector 400 is in the unapproximatedstate, lever 414 a is disposed in an extended position, due to springbiasing forces applied to lever 414 a by leaf spring assembly 412,through contact with engagement tip 412 d of leaf spring 412 a. Drivebeam 426 is disposed in a proximal-most position and leaf spring 412 aof leaf spring assembly 412 is disposed in an unflexed state. In theextended position of lever 414 a, distal tip 414 b of lever 414 a isdisposed in notch 426 d of lateral projecting member 426 c of drive beam426.

With reference to FIGS. 8 and 9, rotation of drive member 416 a rotateshead 424 a of drive screw 424, which imparts rotation to drive screw424. The pair of retention members 424 b maintains drive screw 424longitudinally fixed as the drive member 416 a imparts rotationalmovement to drive screw 424. With drive screw 424 being threadablyengaged with retention foot 426 a of drive beam 426, rotational movementof drive screw 424 distally translates drive beam 426, as indicated byarrow “A.” In this regard, distal tip 414 b of lever 414 a engages anotch sidewall 426 g of drive beam 426, preventing distal translation ofdrive beam 426 and causing lower jaw member 420 to pivot relative toupper jaw member 410 in the direction indicated by arrow “B” and about apivot axis “P” that is defined transversely through head 424 a of drivescrew 424. As lower jaw member 420 pivots toward upper jaw member 410,closing and/or approximating upper and lower jaw members 410, 420, drivebeam 426 engages a bottom surface of lever 414 a so that lever 414 apivots, counterclockwise (as illustrated in FIG. 9, albeit clockwisewhen viewed from the opposite side of end effector 400), toward upperjaw member 410 in the direction indicated by arrow “B” against springbiasing forces applied to a top surface of lever 414 a throughengagement tip 412 d of leaf spring assembly 412. In response topivoting movement of lever 414 a toward upper jaw member 410, leafspring 412 a begins to flex to a flexed state in the direction indicatedby arrow “B” so that leaf spring 412 a pivots, clockwise (as illustratedin FIG. 9, albeit counterclockwise when viewed from the opposite side ofend effector 400), relative to fastener 412 c, toward upper jaw member410.

As seen in FIGS. 10 and 11, further rotational movement of drive screw424 pivots lever 414 a so that distal tip 414 b of lever 414 a separatesfrom notch 426 a enabling lever 414 a to pivot toward a retractedposition and enabling lower jaw member 420 to continue to pivot towardupper jaw member 410, as indicated by arrow “C,” until upper and lowerjaw members 410, 420 are positioned in the approximated state. Uponseparation of distal tip 414 b of lever 414 a and notch 426 a of drivebeam 426, continued rotational movement of drive screw 424 distallytranslates drive beam 426, as indicated by the arrow “A,” beneath lever414 a along the bottom surface of lever 414 a or lever assembly 414until drive beam 426 mounts to ramp 410 j. Distal translation of drivebeam 426 drives lever 414 a to the retracted position in which distaltip 414 b engages a bottom surface of leaf spring 412 a at a point 412 ealong leaf spring 412 a, separating engagement tip 412 d from a topsurface of lever 414 a and enabling drive beam 426 to mount to, andtranslate along, ramp 410 j.

With reference to FIGS. 12 and 13, when upper and lower jaw members 410,420 are in the approximated state, lower jaw member 420 is positioned inparallel with upper jaw member 410, and head 424 a of drive screw 424 issupported within a bore 416 d of drive member 416 a so that drive screw424 is parallel to upper jaw member 410. In the approximated state,continued rotation of drive screw 424 distally translates drive beam 426through end effector 400 toward a distal end portion of end effector400, as indicated by arrow “A.” Upon translating drive beam 426,distally past lever assembly 414, leaf spring assembly 412 urges leverassembly 414 to the extended position. Continued rotation of drive screw424 advances actuation sled 422 through fastener cartridge 420 a to firethe plurality of fasteners stored within fastener cartridge 420 a forsecuring to tissue.

Drive screw 424 can then be rotated in an opposite direction to retractdrive beam 426 proximally to the proximal-most position. Moreparticularly, drive beam 426 is retracted proximally until drive beam426 engages lever assembly 414, which under the spring bias of leafspring assembly 412, urges upper and lower jaw members 410, 420 apart sothat upper and lower jaw members 410, 420 are disposed in the originalor unapproximated state as shown in FIG. 6. Fastener cartridge 420 a canthen be removed, disposed of, and/or replaced, as desired, and theoperation of end effector 400 described above can be repeated asnecessary with a new, un-fired fastener cartridge 420 a loaded in lowerjaw member 420.

In embodiments, end effector 400 supports one or more computer ormicrochips (not shown) that electrically communicate signals oridentification codes to the controller and/or circuit board of surgicalinstrument 100. The signals or identification codes can indicate whetheror not fastener cartridge 420 a, or portions thereof, is at leastpartially fired, unfired, etc.

Turning now to FIGS. 14-16, a drive beam, in accordance with anotherembodiment of the present disclosure, is generally designated as 500.Drive beam 500 is substantially similar to drive beam 426, and thus,will only be described in detail herein to the extent necessary todescribe differences in construction and/or operation from those ofdrive beam 426.

Drive beam 500 includes a composite body 510 that is formed of two ormore materials to reduce input torque for advancing drive beam 500 whileproviding strength sufficient to support loads required to clamp andfire fasteners in thick tissue. Composite body 510 has an I-shapedcross-sectional profile (see FIG. 16) and includes a retention foot 520,a threaded insert 530 secured to the retention foot 520, a verticallyoriented support strut 540 extending from retention foot 520, and alateral projecting member 550 formed atop support strut 530. Verticallyoriented support strut 540 supports a knife 542 adapted to cut tissue asdrive beam 500 translates along threaded drive screw 424.

In some embodiments, at least portions of one or more of retention foot520, vertically oriented support strut 540, and/or lateral projectingmember 550 can be integrally and/or monolithically formed of a firstmaterial, for example, a metallic material such as stainless steel toprovide load supporting strength for clamping and firing fasteners “F”with the presently described surgical devices. In embodiments, at leastportions of one or both of threaded insert 530 and/or lateral projectingmember 550 can be integrally and/or monothically formed of a secondmaterial, for example, a polymeric material such as polyether etherketone (PEEK) to reduce input torque for advancing drive beam 500 asdescribed in greater detail below. As can be appreciated, one or more ofany of the components, or portions thereof, of drive beam 500 can beformed of any suitable material including polymeric and/or metallicmaterials. Persons skilled in the art will understand that one or moreof any of the components, or portions thereof, can be formed using knownforming and/or fastening techniques such as molding, casting, milling,welding, etc. For example, metallic materials of drive beam 500 can becasted and/or milled and polymeric materials can be injection moldedtherein.

As seen in FIG. 15, retention foot 520 defines a threaded bore 522having an inner surface 522 a. Threaded bore 522 includes internalthreads 524 that extend from inner surface 522 a of threaded bore 522.Retention foot 520 further includes a heel 526 extending from a bottomportion of an outer surface of retention foot 520. Heel 526 defines oneor more channels 526 a therein and includes a plurality of wings 526 bextending laterally therefrom.

Threaded insert 530 extends between opposite ends 530 a, 530 b andincludes internal threads 532 and external threads 534 that dependtherefrom. Internal threads 532 are formed on/extend from aninternal/inner surface 530 c of threaded insert 530 and external threads534 are formed on/extend from an external/outer surface 530 d ofthreaded insert 530. Internal threads 524 of threaded bore 522 engageexternal threads 534 extending from outer surface 530 d of threadedinsert 530. Each of internal threads 532 of threaded insert 530 definesan internal peak 532 a and each of external threads 534 of threadedinsert 530 defines an external peak 534 a. In embodiments, each internalpeak 532 a is adjacent to, and longitudinally offset from, one ofexternal peaks 534 a. As can be appreciated, one or more of any of thethreads of retention foot 520 and/or threaded insert 530 can have anysuitable configuration including any suitable shape and/or dimension.

Each of opposite ends 530 a, 530 b of threaded insert 530 includes alocking flange 536 extending radially outward therefrom to fix and/orfacilitate securement of threaded insert 530 to retention foot 520.Threaded insert 530 can include one or more locking tabs 538 extendingfrom a bottom surface of threaded insert 530. Each locking tab 538 issecured within one of channels 526 a of heel 526 to fix and/orfacilitate securement of threaded insert 530 to retention foot 520.Threaded insert 530 can include a pair of wings 539 extending fromlocking tabs 538 that overly the pair of wings 526 b of heel 526.

As seen in FIGS. 15 and 16, lateral projecting member 550 includes acentral portion 552 and a pair of wings 554 extending from centralportion 552. Portions of central portion 552 and/or the pair of wings554 can define a notch 556 formed in an upper surface of lateralprojecting member 550. Central portion 552 can be formed of a polymericmaterial such as PEEK and the pair of wings 554 can be formed of ametallic material such as stainless steel. A bottom surface 552 a ofcentral portion 552 is adapted to engage and slide along ramp 410 j offirst jaw member 410.

In operation, threaded drive screw 424 is threadably engaged withthreaded insert 530 of drive beam 500. Threaded drive screw 424 isrotatable to selectively distally advance drive beam 500 along threadeddrive screw 424. As threaded drive screw 424 rotates, drive beam 500advances similar to that described above with respect to drive beam 426.Lateral projecting member 500, namely bottom surface 552 a of centralportion 552 engages with, and slides along, the top surface of ramp 410j (see FIG. 11) of first jaw member 410 to maintain first jaw member 410and second jaw member 420 in an approximated state as drive beam 500distally translates along first and second jaw members 410, 420. Asdrive beam 500 distally translates, the plurality of fasteners “F” arefired from fastener retaining slots 423 b of fastener cartridge 420 a toform the plurality of fasteners “F” against tissue engaging surface 411of first jaw member 410.

As noted above, threaded insert 530, or portions thereof, can be formedof any suitable polymeric material such as PEEK to reduce frictionforces generated between outer surfaces of threaded drive screw 424 andinner surfaces of threaded insert 530 of drive beam 500 upon rotation ofthreaded drive screw 424. Similarly, central portion 552 of lateralprojecting member 550A and can also be formed of polymeric material toreduce friction forces between bottom surface 552 a of lateralprojecting member 550 and the first jaw member 410 (e.g., the topsurfaces of ramp 410 j), which can be metallic. Likewise, the pair ofwings 539 of threaded insert 530 can be formed of polymeric material toreduce friction forces between upper surfaces 539 a of the pair of wings539 and surfaces (e.g., metallic) of second jaw member 420. Reduction infriction forces between threaded drive screw 424 and drive beam 500;upper surfaces 539 a of the pair of wings 539 and second jaw member 420;and/or between bottom surface 552 a of lateral projecting member 550 andfirst jaw member 410 reduces input torque required to advance drive beam500 along threaded drive screw 424. For example, friction forcesgenerated by plastic-on-metal engagement can be up to two and a halftimes less than a similar metal-on-metal engagement. Given that portionsof drive beam 500 can be formed of metallic material, composite body 510of drive beam 500 provides sufficient strength to support loads requiredto clamp and fire fasteners in thick tissue while simultaneouslyreducing input torque required to advance drive beam 500 along threadeddrive screw 424.

Persons skilled in the art will understand that the structures andmethods specifically described herein and shown in the accompanyingfigures are non-limiting exemplary embodiments, and that thedescription, disclosure, and figures should be construed merely asexemplary of particular embodiments. It is to be understood, therefore,that the present disclosure is not limited to the precise embodimentsdescribed, and that various other changes and modifications may beeffected by one skilled in the art without departing from the scope orspirit of the disclosure. Additionally, the elements and features shownor described in connection with certain embodiments may be combined withthe elements and features of certain other embodiments without departingfrom the scope of the present disclosure, and that such modificationsand variations are also included within the scope of the presentdisclosure. Accordingly, the subject matter of the present disclosure isnot limited by what has been particularly shown and described.

The invention claimed is:
 1. An end effector of a surgical staplingapparatus, the end effector comprising: a first jaw member; a second jawmember adapted to support a plurality of fasteners; a drive beamengagable with at least one of the first or second jaw members, thedrive beam including a retention foot defining a threaded bore andformed of a first material, the threaded bore supporting a threadedinsert formed of a second material different from the first material;and a threaded drive screw being threadably engaged with the threadedinsert of the drive beam and rotatable to selectively advance the drivebeam along the threaded drive screw to fire the plurality of fasteners.2. The end effector of claim 1, wherein the first material includesmetallic material and the second material includes polymeric material.3. The end effector of claim 1, further comprising a mounting portionextending proximally from at least one of the first or second jawmembers, and adapted to selectively mount to the surgical staplingapparatus.
 4. The end effector of claim 1, wherein the first jaw memberdefines a ramp, the drive beam being engagable with the ramp to maintainthe first jaw member and the second jaw member in an approximated stateas the drive beam translates along the first and second jaw members. 5.The end effector of claim 1, wherein the drive beam supports a knifeadapted to cut tissue as the drive beam translates along the threadeddrive screw.
 6. The end effector of claim 1, wherein the threaded boreincludes internal threads that extend from an inner surface of thethreaded bore and engage external threads extending from an outersurface of the threaded insert.
 7. The end effector of claim 6, whereinthe threaded insert includes opposite ends, wherein at least one of theopposite ends of the threaded insert includes a locking flange extendingtherefrom to fix the threaded insert to the retention foot.
 8. The endeffector of claim 7, wherein the threaded insert includes internalthreads extending from an internal surface of the threaded insert, theinternal threads are threadably engaged with the threaded drive screw.9. The end effector of claim 1, wherein the drive beam includes alateral projecting member, wherein at least portions of the lateralprojecting member are formed of a polymeric material.
 10. A poweredsurgical stapling apparatus, comprising: a handle assembly; a shaftassembly extending distally from the handle assembly; and an endeffector selectively detachable from the shaft assembly, the endeffector including: a first jaw member; a second jaw member adapted tosupport a plurality of fasteners; a drive beam engagable with at leastone of the first or second jaw members, the drive beam including aretention foot defining a threaded bore and formed of a first material,the threaded bore supporting a threaded insert formed of a secondmaterial different from the first material; and a threaded drive screwbeing threadably engaged with the threaded insert of the drive beam androtatable to selectively advance the drive beam along the threaded drivescrew to fire the plurality of fasteners.
 11. The end effector of claim10, wherein the first material includes metallic material and the secondmaterial includes polymeric material.
 12. The end effector of claim 10,further comprising a mounting portion extending proximally from at leastone of the first or second jaw members, and adapted to selectively mountto the surgical stapling apparatus.
 13. The end effector of claim 10,wherein the first jaw member defines a ramp, the drive beam beingengagable with the ramp to maintain the first jaw member and the secondjaw member in an approximated state as the drive beam translates alongthe first and second jaw members.
 14. The end effector of claim 10,wherein the drive beam supports a knife adapted to cut tissue as thedrive beam translates along the threaded drive screw.
 15. The endeffector of claim 10, wherein the threaded bore includes internalthreads that extend from an inner surface of the threaded bore andengage external threads extending from an outer surface of the threadedinsert.
 16. The end effector of claim 15, wherein the threaded insertincludes opposite ends, wherein at least one of the opposite ends of thethreaded insert includes a locking flange extending therefrom to fix thethreaded insert to the retention foot.
 17. The end effector of claim 16,wherein the threaded insert includes internal threads extending from aninternal surface of the threaded insert, the internal threads arethreadably engaged with the threaded drive screw.
 18. The end effectorof claim 10, wherein the drive beam includes a lateral projectingmember, wherein at least portions of the lateral projecting member areformed of a polymeric material.